Signaling system



Jam., 9, 1923 SIGNALING SYSTEM. man JULY 7. 1920.

0. B. BLACKWELL.

3 SHEETS-H551 1.

ATTORNEY 0. B. BLACKWELL. SIGNALING SYSTEM.

Jan. 9, 1923.

3 SHEETS-SHEET Z.

FILED JULY 7,1920.

Jam.. 9, 1923 0. B. BLACKWELL.

. SIGNALING SYSTEM.

FILED Jun/7.1920.

3 SHEETS-SHEET 3.

INVENTOR WWW llilatentedl lily llthlltlt application filed .Tuir 7, 1920.

To (zi/Z w/"io'my 'it may concer-n:

Be it lrnown that l, 'r'ro B. BLACKWICLL, residing at Garden City, in the count7 of Nassau and State of New `ilrorl, have invented certain Improvements in Signaling Systems, of which the following is a specification.

This invent-ion rela-tes to signaling sys teins, and especially to means for generating a voltage wave having the ilorin best adapt ed for signaling over circuits characterized by great distortion and attenuation, such as submarine cables, and for applying` such waves in the inanner best adapted to obtain greater operatingl elliciency.

.ln the operation ot sulnnarine cables it is customary to use a code for transinittinfi signals in which an iinpulse in one direction represents a dot and an inipulse in the other direction represents a dash. lizleretotore, it has been customary tol use a battery as the source oit signaling` energy, a dot being represented by an impulse ot one polarity, and a dash by an impulse ol opposite polarity, ln order to prevent interference with the duplex balance, it has been customary te insert an impedance in the sendingcircuit so as to round ott the waves. '.lhese ini-v pulses may also be obtained by means ot a sine wave generator in which each halt` wave represents an impulse.

its 'well known, after an impulse has been sent into a. cable there persists tor a varyingi period thereafter a charge in the cable which causes distortion or the subsi quent si} rnalin .gl impulses. in order to cor` rect this trouble it has been proposed to send out what are known as Curbed signals in which at the end ot each signaling; iinpulse another impulse oi lesser magnitude and in the opposite direction is sent into the cable, the function oit which is to neutralize the residual effects et the prior signaling,` iinpulse, ln all oit the foregoing `methods et signaling', the transmittal et each iull inipulsa whether curbed or not, niust be entirely finished betore the next signaling.'` iinpulse is impressed upon' the cable7 which slows down the speed ot transmission ot sigriials.

@ne ot the objects ot the present invention is to overcoine the attenuating and distort`H ingr eiiects which characterirf:'A the trans)nis.n sien ot signals over sulnnarine cabi by providing Ymeans for the production or Eleral lilo. wiel-Wel.

voltage wave which will have the forno best adapted to give the desired arrival wave at the distant end and to cause the least interterence in the duplex balance.

Another object et this invention is to provide :method and ineans for applying to a cable circuit signaling waves oi" the toregoing type without reducing` the speed of transmission, which method is characterized by the continuance of the application of each signaling' wave for a limited period after the beginning oit the application et succeeding signaling wave or waves, which insures sending into the cable simultaneously with each signaling impulse another voltage wave which tends to overcome residual ettects or' prior signaling impulses.

rlhis invention will be better understood ,troni the following description when read in connection with the attached drawing oi which Figure i, represents a forni of voltage wave which is typical ot that class best adapted for submarine cable telegraphy; iligrures il and 2 represent one nieans for generating; the desired voltage; wave such as shown in Figure l, and Figure 3 shows another ineans for generating such type olf wave; liieure llshows an arrangement b v means of which the wave set up by either of the foregoing genera-tors may be applied to the submarine cable in the manner best adopted to overcome the residua-l eiliects oi? the cable vupon successive signaling1 inipulses; and Figure 5 shows graphically the type et transmitted were resuiting` troni the application. et a pluralityv oi signals to the cable.

'the curve c shown in ltigure il represents the torni oit a wave which is typical of a class best adapted to nfieet the requirements ot' submarine cable signaling. The Ltorrn et such a wave may be determined bv rneans of the equations set lortli in the copending application or Carson7 Serial Num* ber 3 -tlO7 tiled duly 7, 1920. Although thel wave shown in Figure l consists ot' three halt-cycles, it is to be understoodthat the number may be increased or diminished wit-hout departing trein the scope of this invention.

Experience has shown that it is dillieult to desinn a generator which would be capa ble o'f'f producing a volt Oe wave the torni et which :is shown in l* ure l, which wave would have sufficient energy to be used dinaiing. In Figure 2, l represents :in eieetroiap'net the poie 'faces of which are brought close together so that the Width et the slot 2 will he tiiCient for the passage therethrough 01"'. the rehitiveiv narrow rotor which is a continuous strip oit mrmetie material. The pele taees are so d that one of the dimensions 17 very small as compared with the 4.- mension 1S. The rotor B, is so des that it will, in the course ot rotation about its axis 1G, vary the reluctance et the mag'n netie circuit of the maglieL i in accordance with a certain predetermined seheme Whieh depends upon the desired 't ,rm oit' the ontput Waves. Thus it will he seen that 'the contour of that part et the periphery ot the rotor 3, which moves between the uppe and lower limits of the gap (represen hy the distance 18), varies inA accordance with the form of the desired output voltage weve. Consequently the reiuetenee o'i the magnetic path is going to Change r-:ith the variations in the cross section et the rotor as it moves through the gap. The ifitions in the flux in the magnet Cere 'l proportional to the variations er the torn out the roter and Consequently the vrdtueje weve set up in the Winding` 4- Wiil have the predetermined Wave form. Such an output Wave has substantially no ene and in order to render it available for si @nel e purposes it must he passed three i tortionless ampiiiier 5 such as, tor eti-amp y the Weil. known vacuum tnhe. Fi nire E shows in detail a part oi the gene olf Figure 2 which makes rieur the typering ot the pole tziees in order to pre row gap, 2, throi'igh whirh the rotor f3 mov..-

:it suhstantialiy uniform speed. 1t si be stated that the .roter shown in ii 2 is adapted to produce two waves .in

revolution. This, however, may he ve iel so as to produce a `greater or ies number ot Waves es partieuhir eenditio' may require.

Figure 3 represents another terni o? rangement to generate a Wave oi desired form and to give to such Wave amount of energy. n the ii" le. (3 rei. sents the disc of magneti@l 'materiel which is adapted to he rotated around the axis T. Arranged in eiose jliiztzngosition to the periphery of the dise are magnets, .Q The Winding` ot' the me therewith :i hzittery 'ih sistenee l1.

:i r The movable erm l reines' Variable resistzznee which is pivoed :uy 13 is adapted to nieve up and down, in consequence et the n'ivfnenient ot the roller lll upon the cam it will he seen that :i\4 the Cain, nihiih has thri'orin siinuiuiinggj ihn ii'orm oit the desired outputv n'ure, is niorrd 'in the direction un h r the airron', ihn urm lf2 n'iii he moved up :1nd down, ther/ehr uryii'ig the re stance il in the ii-ruit which einhrziee ti e magnet ti. The ruirenl tien' J'h Winding;v oi this nniuuei will he i ed in aeCorduinfe with the d sired nieve torni und the resuitaut iin); will magnetize the dise (i Whirh inowff in s rnehronisin with the cani fis the dise ro tetes it Wiii iinhu'e in the voit ot the nnufnri a Veltins were hziriinr .snlistzuuuiy the torni repii'fsffnted iff the mun il?. 'thnoliflh :in :nnpiiiirr W uinpiiiiod to the required he impressed upon the outgro rouiiih the (zeiler/er 'ervith instead of Ytwo :is rIhe nnigiieis` shon'n the seid ligure. numbered i6, 1'( and 1S, :ire designed to produce a voitege rrare haring; the raw form Correspending,r to the nnignetimtion o' the moving dise Q() hy menus of the maglie'. i9. Con ieeed with tin` suine shun Whieh i'otutes the disil QV :1ro the :ii-nn'. 2i :e iinpuhfw, i'lisirihutors :uid i' these dis iiutni's hns ihren arrangement i' f: cation oi rnin i. J. SO ihm n., 'in

`\ ENh :ire onlinr-ted with the rv C ,fiu'itdlilff derives S1.. #il und HI,

ot 'th The rotatinu arios Q1 und :ire onnerfvd with the armatures and QG oi" rei-.lys which muy he eontroiied hv :infr wel] iinonn tape tr3.nsmittingi` device. The switches fi, S2 and S3 consist respwftively ot i'our rr lays eonneeted in groups oi tiro ezufh, n'hirh are adapted to operate :irnnitures QT und QQ, Q9 and 9s Eil und The :irmul'ures are norme iiy connected in series with the input side et the er piii'ier The :inner roni 4. .e f l. i! 4.

@,aeis oi. the ainnunres oi he snitrhes im und 91..., are eonneeted tiin'iiher :nid siniiiziii'x' the ione Colitzufts. iiridnrd :irrof-l the rgper :ind .iovrer rentznfis ot eurh of' the vid v imiinn'iod "iris iii, .i7 ot tie generating;- dern-,e

llo

G1. lhe output side of the amplifier rtg is connected with the midpoint eti the du plei; balanced arms ol the submarine cable network.

Having1 in mind the foregoing descrip tion et the parts ci the apparatus and the runctions `ol2 each, this invention will oe better understood 'from the 'following dcscription ot its mode et' operation. Let it he assumed that the disc 2O has heen mag netized so as to he capable of reproducing e voltage wave oi desired torni, and that the .magnet 19 is adapted to sustain this n1agnetisationV of the disc 20, since -the cam moves in synchronism with the disc. rlhe disc 20 is connected by means ot the shaft 33 with the contact arms Q1 and 22 oil the distributors 28 and 2l and also with the tape transmitter (not shown) which controls the operation ot the armatures and 26 so that ell oit these elements will he synchronized. lt will he seen that similarly located segments et the two distributors are connected with the relays el the same switching` device, that is to say, the seg n'ients 34 and 35 et the distributors 23 and 2l. respectively, are connected with the relays 3G Land 37 oli 'the switching device SL. rlhe relays ot the switching devices @1, S2 and S3 are polarized so that when their armatlilres are moved to an)7 position they remain in that position until an impulse passes through .the relay so as to move the armature to another position.

liet it be assumed that the direction el rotation el the arms 2l and ot the distrihntors is in the direction indicated by the arrow and that they have reached the points and mi at which the said arms begin to make contact with the segments Bil and Due to the synchronous open ation oit.' the parts, the disc 20 will he at this instant in such position as to hegin inducinn; in the windingv oit the net l@ the h *"nning of the wave repre ited hv aal on the cam ot the `generatinil des ice. lle tliermore let .it he assumed that when the tape transmitting device is positioned to tiensinit a dot, the corresponding positions of the armatures and 2G is such that armature 25 closes its upper contact and armature 26 its lower contact. ccordingly e positive impulse will he 'transmitted 'trom the battery B1., over armature corr tact oit.' arm 2l and segment Sil, and through the windings ol' relays 36 and in series and conductor l() to cattery B1. rl'he di reetion et the current through the relays El" and will he such to maintain the armati'lre 27 in Contact with upper contact. Likewise a negative impulse will transmitted trein the battery El over the lower coi ct et armature 52S. contact et ,aiment through the winst arfn witoL p nd et) 1n series and conotf relays 3'! All doctor l0 to battery lll. rlhe direction ol current 'from the relays 3?-39 will he such as to move the armature 28 to its lower contact. llrccordingly the voltage wave which is set np in the winding; of the inagnet l@ will be impressed across the conductors lll and. 4t2, end eventuali;7 will he impressed across the input side of the enr ijlliiier tu The wave amplified will he impressed upon the submarine cable lil. Such a weve is shown by the curve e in Figure 5. rlhe spaces l, il, 3, etc., represent the period oit time required for the arms or to traverse coi-respending` segments of the distributors. ils the :uni nieves aloi'i;v the segment Sil the voltage will rise and tall as shown in column l oit Figure 5. This port et the wave represents the transmission oit dot signal into the cehle.

E move into conllli/hen the arms a i tact with the succeeding' segments il'l and tflicriectively oi the die rihuters, the pe nennt er, which syi'iehronined with the dlstrihu ors. will he p ioned to send, for another dot l into the cahlc.

i' 'the nrn'intines and 2G will the sa. ne position they were 'eegrueni';ly9 there results the a positive impulse from. .i armature i215. the Contact of nient .t, the windings of rclys and ll ries and conductor Ll0 to attery which maintains the sirinature 3 tact. Also the 'transmisiinolse from the battery 26, the contact el erin .1 l` through the windings oli re n series and conductor lfd to battery will cause the :irmatr-.re 30 et the relays to move to its lower contact This il connect the circuit el? the windl ol' p the eondiflctors t9 and 50. tance the dise El() is synchro iff/ed with roto the arms l said disc 'unive in the urina t; und lil w h the :se=inents t-E sind dei.. and consequentlv :i volta y ware such as .is rciinescnn-d ht* t et iti c will i to he impressed across the input si'le ol' amplilier rtw and, as emplit-i' ,.9 vill le protecci upon the cable lll. fhnce the relays he :resumed transinitter tape is designed to send vh means that armature u to its lower Contact and erinnure is to its uppe-- contact. Accordingly ne "if zinsnntted from hutt Ji ure 25, 'the contact of erin the relays 53 und 55 and ery ll, moving the irrinu- 1 mind rela s o' switch S1;

l braced in column 3 will he nice parts of Waves et and o which fire beingtransmitted into the cable snnn with the tunsniission of the signuline in pulse fit curve Tet he assumed that the tape is punched so as to produce zi space in the transmitted signals. Accordingly the armatures Q5 und 26 'vill hoth he moved to their uppeil contects und :t positive impulse will he transmitted over the grins 2l und 22 und the seg:-

inents spondn und 35 resi' ectireljf; to the corregroups oiu relays of the sn'itel-ting' is a result of this the armatures o are moved to their upper contacts and accordingly the potential set up in the Winding of the magnet 16 cannot be inipressee across the anipliiier A3 since one olf sides of the circuit open. r`heretoi"e nn sifgnzilii npu ezthle durii in( the, col" lie seen thut l continueJ to transmitted into the cable.

fl l, 072 und f represent ine curves o lirce niere signaling Waves which are 21p- :Nhle as the result oi the oper"- heo controlled by iinpulses i3 V.:Insinitter in the nninni should he understood, o

l .t ,i e t hor-eli these signaling` iinntlses :ire appli as seperate impulses, tlrejyY ed und vthe actual :torni oit were e fehle is that represented h): e 'nui of the impulses Yfrom isire. 'ill lie, seein become merged impressed on th if/7 which is th great distortion und attenuation und te innplify those Wares Without distortion so :is le give suon energy us is necessary tor purposes of transmission lt will further lie .seen thnt, this invention ulso provides ineens tot leuring' ont the residual charges resulting); from the trunsir'ssion oit siinnili'iu' impulses, thereby ninnniiraing the ii rtion olf suhfse quent signaling` impulses that `generully re suits frein the presence of such residual charges.

Jil-though this invention has heel dirclosed in ce1-tuin specitie torni it to lie understood tht it not so limited, hut is enlJulJle ci cnilmdiinent in other und dilleient forms within the scope ol the :linneiuleil chiiins.

lllhzit is chiinied is:

l. ln n, signaling' system the eoniluinuticn of u niultiphese generator :nluptefi to produ a iroltzige nuire huring :i certain pre determined forni, :t line circuitT und switching nie: ns controlled hy smid generator :uluptetl to spply the Suid n'uff to the, sui-1l line #iin cuit when f-suid roltup'e reziehes u prmleterinined reine.

In n ailing sj,'steni the coznliinution ol: zi inultighuse gener-titel.' :tempted to pro duce :1 voltaire n'uve limiting;- :i eert-.iin predeteri'l'iined ttorzn, :t line circuit5 ineens l'nr :nnplii'jving Suid voltage were und sn'itthintr ineens controlled hy said ,ennerzitoi :idziptetl to :apply seul 'mire to smid line circuit when sziiil roltuge, rmt-lies u predeteiniined railue.

S. ln u signaling system the enniliinzitinn et e ninltipi isc geneiutor5 u plnrulity ol' s i'itches, :ind ineens lor controllingr the operation oit the said switches, the sziitl eontrolling ineens being operated in definite time relationship with said generating whereby the periodv of application et the voltage waves muy l e aiutoinriticaillyv controlled.

'l. ln u signaling' system the enniliinntion olf :i innltiphuse :cinici-tutor` :i plui'uiity el. switches, und impulse trunsiniiling menne epernted in definite tiine relutioinhiie ltr `v:fil generator whereby euch ot siiitl switehef he operated :it certain pi'edetei'niineil tunts oit" time. in a. signaling-1' system the eoinliinution of :in alternating current generutort/ n pluizility of relay operutcd switcher:` :i tape c nti'olled im. `re sender7 :i plurality nl segn'ientzil distrinntors connected n'ith'suid generator adapted to control the operation ol the suie switches in predeterinined order nf'herehj,T the Yoltziee mire nl' the said `enerzttor niiy he applied to :i circuit :it pre,- tleterinincd intcrif'uls.

(i. ln :i sig-ntiling` systemT the roinliinulicni ot :ilon' enerfff t: nei-:ttor desiened lo nreduee u unsoidzil alternatingh mllugge Juve lnifinu the 'lioTni (if :i dumped unie for tzinsniission over long efihle circuits characterized by ditortion und zittenuiztion.

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refines-r distortionless means to amplify to a predeteru'iincd degree the generated wave, and means to apply the said amplified wave to the said cable circuit when the wave reaches a predetermined instantaneous value.

7. ln a signaling; system comprising a `generator of multipliase voltages,` a line cir cuit, a plurality oil distributors each having a rotatable contacter' and at least as many segments as there are phases ot voltages, a plurality ott electro-magnetic switches in* dividual to each phase of said generator, and a transmitter controlled in time ot operation by said 2generator to apply an im pulse to the contactor ot one oit said disa tributors whereby said impulse may be applied at the proper insta-nt to one ot said switches to cause the application of one ot said voltage waves to said line circuit when the said wave is oi predetermined magnitude.

Si. ln a signaling system, the combination with a generator adapted to produce a succession o'F trains ol.z damped waves liar/ing,` definite 'form and a definite damping constent, a. ,line circuit, an amplii'ier, a plurality ot electro-magnetic switches each of which is adapted to connect one train oi waves to said line circuit, a plurality ot distributors operatively connected with said generator, a signal impulse sendingr device also operatively connected with said genm crater whereby the said switches may be controlled at definite times by said irnul vc trains 'to said line ls equal to one-halt ot a multipliasc alternating current source adapted to produce damped waves ot pren determined 'form and ware length7 a line circuit over which said waves are to be transmittcdj a signal impulse sanding` mechanism designed to operate on the principle that dots and dashes are represented by impulses ot opposite polarity, a plurality ot switches controlled :by impulses troni. the said impulse sending' mechanism to ap ply said waves to said line circuit7 and distributing` switches to control the time oi application ot the said impulses to the proper switches.

10. ln a system characterized by the means set Yforth in claim 9, the method o'lf trausinitti C) mum distortion, which. consists in @generating;` multiphasc alternatingl currents having a definite damping constant, amplitying the said currents and impressing' these currents upon a line circuit at intervals ot one halt a wave length apart and controlling the polarity ol the applied wave in accordance with the predetermined signal.

in testimony whereof, l have signed my naine to this specification this 6th da of duly7 1920. i

,fr telegraplfi signals with a niinif 

